To prevent microbial spoilage, a hot fill process is often used to package many food and beverage products at high temperatures to sterilize both the product and container. When the liquid content of the container cools, it contracts and either creates an internal vacuum or causes the container to deform, as by shrinking, buckling or paneling. Currently, plastic bottles are designed with panels, ribs and additional resin to compensate for the contraction and prevent bottle deformation. When the smooth side wall of the bottle is replaced with these panels, flexible packaging shapes and designs are prevented, thereby making label application difficult.
Known approaches to the bottle deformation problem add a gas, such as carbon dioxide or nitrogen, to the bottle after sealing. U.S. Pat. No. 7,159,374 discloses an active insert device that contains a reactant and that is affixed to the bottle cap. After sealing the reactant is initiated to a reaction that produces the gas, which is delivered to a headspace of the bottle. The active insert device includes a membrane that admits moisture from the bottle contents into the active insert device to initiate the reaction. The resulting gas then passes through the membrane into the headspace of the bottle. There is a risk that the membrane will loosen and fall into the bottle and contaminate the bottle contents.
Thus, there is a need for a method that releases gas in a closed container to retain microbial stability without leaving a residue or a device that must be removed at time of consumption.
There is also a need to eliminate buckling or paneling in closed hot filled containers in order to capture decorative, lightweight and flexibility benefits.
There is also a need to sufficiently pressurize a closed hot filled container in order to capture structural benefits without deforming the container.
There is a further need to release ingredients and functional components to closed containers on a time delayed basis to enhance functionality.
There is still another need for a container in which gas can be released to pressurize the container after the container is sealed.
There is yet another need for a closure or cap for a container that can release gas into the container after sealing to pressurize the container.
There is yet a further need to substantially eliminate any residue from the active insert device from entering the compartment.